Radio communication capable devices must meet several different purpose requirements. Reasons are typically derived from standards, product requirements, type approval requirements, functional requirements for correct assembly and other safety regulations. Recently radio network and other communication have been introduced to a variety of different devices, for example, it is common that modern consumer electronics, including automotive, may have a plurality of devices that are capable of communicating wirelessly. In practice any modern electric device may be capable of communicating wirelessly. As an RF radio module as such may be a small portion of a device it is reasonable to manufacture RF radio modules that are placed into a host device. This kind of host device may be smartphone, tablet, water meter, electric power consumption meter or other similar special purpose device having wireless communication capability.
Wireless communication radio modules, such as RF and BB blocks, are tuned, aligned/calibrated and tested in production in order to take into account active and passive components, signal delays, printed wired board, interfaces, product configuration characteristics, application characteristics and requirement deviations that may be caused by the host device, where module will be taken into use. Baseband (BB) calibrations are performed, if necessary, to make HW platform to fulfill functional and performance requirements. These may be for example energy management calibrations and/or ADC calibrations for accuracy improvements. The electrical performance of the RF components varies a lot by nature. The objective of the RF tunings is to calibrate away this natural variation so that regulatory requirement for electrical performance and product requirements can be met. RF tuning is a process by which values for specific compensation parameters used inside the RF device driver, firmware or other special purpose electrical blocks are determined. Calibrations are performed to align RF performance to a predefined acceptable level which otherwise would not be achievable due to sample to sample variations of RF components. The number and type of parameters that need calibration are different for each RF architectures and RF system implementations. Some general examples of special purpose calibration parameters include RX AGC parameters (e.g. for 2G/3G/LTE), TX power parameters (e.g. for 2G/3G/LTE), AFC parameters, interoperability parameters and other special purpose parameters for performance improvement. RF tunings may be done either with external test equipment or by using a special purpose self-tuning methodology built in the hardware. The number of tuning values in an RF radio module depends on the number of supported communication systems, supported bands, number of receiver paths, number of transmission paths, supported band widths, data classes, antenna interfaces, interoperability requirements, tunable special purpose components e.g. filters other non-cellular wireless systems supported in same module/device, shielding arrangement etc. Tuning values may be stored in ASCII-format or other special purpose format, which is defined by system architecture. It is understood that the number of needed tuning/calibration values and format have requirements to the needed size of memory.
In different phases of production chain there may be testing phases, which may validate functionality, calibration values validity, assembly verification etc.
Appropriate tuning values are essential for fulfilling requirements mentioned above. For example, if host device would not pass type approvals without appropriate tuning values the host device could not be sold for public before tuning and/or calibration. Tuning and/or calibration test results and values are used to define and calculate each special purpose tuning values for each device in volume production. The correct tuning values are stored in a memory within the RF radio module. Typically the memory may be a flash memory or corresponding non-volatile memory. As the tuning values vary between different modules and devices where modules are used, there may be a need to store a plurality of different tuning values that are identified, for example, by using a production ID, product code or similar special purpose identification method. These production ID's may contain numbers, alphabetical characters, figures or it may be special purpose combination of methods.
As above mentioned RF radio communication modules/modems are a common component in modern technology. Thus, there is a continuous need to make them cheaper, smaller and more flexible in order to facilitate better into host device design with cheaper construction.